• Journal of the Society of Disaster Information
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• v.15 no.3
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• pp.427-439
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• 2019

Purpose: We generated geospatial information of unmanned aerial vehicle based on various SW and analyzed the location accuracy of orthoimage and DSM and texture mapping of 3D mesh. Method: The same unmanned aerial image data is processed using two different SW, and spatial information is generated. Among the generated spatial information, the orthoimage and DSM were compared with the spatial information generation results of the unmanned aerial photogrammetry SW by performing quantitative analysis by calculating RMSE of horizontal position and vertical position error and performing qualitative analysis. Results: There were no significant differences in the positional accuracy of the orthoimage and DSM generated by each SW, and differences in texture mapping in 3D mesh. The creation of the 3D mesh indicated the impact of the Unmanned Aerial Photogrammetry SW. Conclusion: It is shown that there is no effect of SW on the creation of orthoimage and DSM for geospatial analysis based on unmanned aerial vehicle. However, when 3D visualization is performed, texture mapping results are different depending on SW.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.239-246
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• 2019

The drone photogrammetry is actively utilized for obtaining highly accurate spatial information and other various monitoring purposes. It is general to plan the drone photogrammetry by referring to previous experiences or cases in order to obtain the required accuracy, but the drone photogrammetry is often carried out again due to poor accuracy. Since the required spatial accuracy of the drone photogrammetry process result becomes the means of objective evaluation regardless of the type of result, it should be determined carefully. Therefore, it is necessary to determine flight height, overlap, number and arrangement of ground control point, and exterior orientation factor acquisition method in order to meet the required 3D positional accuracy for the design of drone photogrammetry project. In this study, previous study cases for the analysis of drone photogrammetry accuracy were carefully analyzed and verified by applying such cases to testing area, and design guideline of drone photogrammetry project for a small area was prepared based on the analysis result. The presented project design guideline is expected to be a great help to business practice although it is not perfect, and if the design guideline is prepared through comprehensive analysis in future, it would be possible to provide a perfect manual.

• 시스템엔지니어링워크숍
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• s.4
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• pp.146-150
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• 2004

The Tactical Data Link System(TDLS) is a standardized communication link to exchange and interface positional, situational information, command and control in real time. It has been evaluated that the link would play an important role for tactical interoperability, situation awareness, and execution of joint operations in the future war. This work presents how to embody the TDLS through the systems engineering approach on the base of TDLS operating concept analysis of helicopters-groud units.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.765-768
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• 1995

A double parallel manipulator has only two or three links in each parallel mechanism. this reduces link interferences so that we expect a large workspace. To prove this property, this paper analyzes the workspace of a double parallel manipulator and compare it with that of a Stewart Platform. the analysis is separately conducted in a positional and an orientational division. For each, we obtain the workspace accrding to the ranges of lengths of links and show the volume in a cartesian coordinate or the angular ranges in yaw and pitch motions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.336-342
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• 1994

This paper presents an useful technique for assessing the volumetric error in multi_axis machine tools using the kinematic double ball bar and 3 dimensional spherical contouring. The developed system proposes the 3 dimensional spherical contour for the error analysis. The developed system input the measured radial data, analysing the volumetric errors such as positional, strightness, angle, and squareness errors, etc. The developed system has been tested in a practical machine tool, and showed high

• Progress in Medical Physics
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• v.26 no.3
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• pp.143-152
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• 2015

In this study, we aim to design the architecture of the kV imaging system for tumor tracking in the dual-head gantry system and analyze its accuracy by simulations. We established mathematical formulas and algorithms to track the tumor position with the two-pair kV imaging systems when they are in the non-orthogonal positions. The algorithms have been designed in the homogeneous coordinate framework and the position of the source and the detector coordinates are used to estimate the tumor position. 4D XCAT (4D extended cardiac-torso) software was used in the simulation to identify the influence of the angle between the two-pair kV imaging systems and the resolution of the detectors to the accuracy in the position estimation. A metal marker fiducial has been inserted in a numerical human phantom of XCAT and the kV projections were acquired at various angles and resolutions using CT projection software of the XCAT. As a result, a positional accuracy of less than about 1mm was achieved when the resolution of the detector is higher than 1.5 mm/pixel and the angle between the kV imaging systems is approximately between $90^{\circ}$ and $50^{\circ}$. When the resolution is lower than 1.5 mm/pixel, the positional errors were higher than 1mm and the error fluctuation by the angles was greater. The resolution of the detector was critical in the positional accuracy for the tumor tracking and determines the range for the acceptable angle range between the kV imaging systems. Also, we found that the positional accuracy analysis method using XCAT developed in this study is highly useful and will be a invaluable tool for further refined design of the kV imaging systems for tumor tracking systems.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2332-2338
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• 2011

In this study, we proposed a new promising idea of utilizing moving window principal component analysis (MWPCA) as a sensitive diagnostic tool to detect the presence of peak position shift. In this approach, the moving window is constructed from a small data segment along the wavenumber axis. For each window bound by a narrow wavenumber region, separate PCA analysis was applied. Simulated spectra with complex spectral feature variations were analyzed to explore the possibility of MWPCA technique. This MWPCA-based detection of the peak shift, potentially coupled with 2D correlation analysis to provide additional verification, may offer an attractive solution.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.11
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• pp.138-147
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• 2001

Alignment systems are frequently used under various semiconductor manufacturing environment. Particularly in PDP(Plasma Display Panel) manufacturing process, the alignment system is applied to the combining and sealing processes of the upper and lower glass panels of PDP, where these processes are performed in the vacuum chamber of high vacuum and high temperature. In this paper, the XYΘ-alignment stage is developed to align PDP panels. Because of high vacuum and high temperature environment, the alignment chamber has been designed to isolate the inner part of the alignment chamber from the outer environment of high vacuum and high temperature, in which every part of the alignment stage is inserted. As it is difficult to attach feedback sensors to the alignment stage in the alignment chamber, the alignment stage is implemented with the open loop algorithm, where the parallel link structure has been designed using step-motors and ball-screws for structural simplicity. The kinematic analysis is performed to drive the parallel link structure, based on the experiments of actuation-compensation of the alignment stage. For the error compensation, the hyperpatch model has been used to model the errors. From the experiments, the positional accuracy of the alignment stage can be improved significantly.

• Journal of the Korean Home Economics Association
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• v.30 no.4
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• pp.231-247
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• 1992

A Study on Maternal Verbal Control Patterns and Children's Recognition against those. The primary objective of the material presented in this dissertation is the analysis of the maternal verbal control patterns. The major focus is given to the differences between maternal verbal control patterns and children's recognition against those. The purspoe of this study were; 1) to investigate the maternal verbal control patterns recognized by children according to their family and personal surroundings; 2) to investigate the verbal control patterns in mother's response according to the differences of family and personal surroundings; 3) to find the differences between children's recognition and maternal verbal control patterns; 4) How the maternal verbal control patterns recognized by children are? The materials of this study were 81(37; boys, 44; girl)) from kindergarten in Seou. The sample of age used in this study was 5 to 7 years old. The test about maternal verbal environment used the question sheet for reaction between mother and children by Gumperz. The kids got interviews with same questions as mothers with question sheet. The statistical tools used is the analysis of the data were frequency, crosstab, and t-test. The result of the study were summarized as follows; 1) The maternal verbal control patterns recognized by children had differences according to whether living with grand-parent or not. Living with grand-parent are more person-oriented than without grand-parent group. 2) The maternal verbal control patterns of mother response show the differences within mother's academic background, present situation of child, and parent's expection to child. The imperative verbal control pattern was more frequently used of low academic background who just fraduate the middle or high school. The personal verbal control pattern was more frequently used of high educational background's like university graduate or more educated group. 3) The differences between maternal verbal control patterns with children's recognition and with mother response is that mother responseis more person-oriented than children's. 4) The imperative verbal control pattern used command, verbal purnishment, and physical purnishment. the status-oriented verbal control pattern used univesal positional appeals and limited positional appeals. The person-oriented verbal control pattern used child-oriented cognitive affective appeals.

• Journal of Audiology & Otology
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• v.23 no.1
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• pp.8-14
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• 2019

Background and Objectives: This study aimed to analyze risk factors for positional vertigo (PV) and the influence thereof on daily life and subjective quality-of-life (QoL). Subject and Methods: A cross-sectional study was conducted using data of the 2010 Korea National Health and Nutrition Examination Survey. The study population consisted of 1,274 individuals aged >40 years for whom complete dizziness-related data were available. Blood and urine tests were performed, and nutritional intake, QoL, and subjective health status were measured using a questionnaire. The associations between PV and blood/urine test data and nutritional intake were evaluated via multiple logistic regression analysis. Results: A history of PV within the previous year was reported by 98 individuals (7.7%). Advanced age and female gender were both significantly associated with such a history. Serum hemoglobin, creatinine, and triglyceride levels correlated significantly with a history of PV. Carotene, vitamin A, and vitamin B2 intakes were significantly lower in individuals with PV. Multivariate analysis revealed that only age was significantly associated with a history of PV (p=0.003). Although subjective health status score was not significantly lower in subjects with PV, subjective impairments in mobility, self-care, the performance of usual activities, and anxiety/depression were more prominent in individuals with PV. A fall history and limitations of activity were also significantly higher in individuals with PV (p<0.001 and p=0.003, respectively). Conclusions: Age was a risk factor for PV, which affected most QoL parameters, fall frequency, and the performance of normal activities.